Implement a system resources management routines

2024-05-16 23:08:59 +02:00
parent 058649036f
commit 74c1b03a6b
8 changed files with 297 additions and 0 deletions
--- a/xtoskrnl/ke/sysres.c
+++ b/xtoskrnl/ke/sysres.c
@@ -0,0 +1,214 @@
+/**
+ * PROJECT:         ExectOS
+ * COPYRIGHT:       See COPYING.md in the top level directory
+ * FILE:            xtoskrnl/ke/sysres.c
+ * DESCRIPTION:     Builtin system resources management
+ * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
+ */
+
+#include <xtos.h>
+
+
+/**
+ * Looks for an unacquired system resource of the specified type and acquires it.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+KeAcquireSystemResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                        OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    /* Acquire system resource */
+    KepGetSystemResource(ResourceType, TRUE, ResourceHeader);
+
+    /* Return status code */
+    return (*ResourceHeader == NULL) ? STATUS_NOT_FOUND : STATUS_SUCCESS;
+}
+
+/**
+ * Looks for an unacquired system resource of the specified type and returns it without acquiring an ownership.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+KeGetSystemResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                    OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    /* Get system resource */
+    KepGetSystemResource(ResourceType, FALSE, ResourceHeader);
+
+    /* Return status code */
+    return (*ResourceHeader == NULL) ? STATUS_NOT_FOUND : STATUS_SUCCESS;
+}
+
+/**
+ * Releases system resource.
+ *
+ * @param ResourceHeader
+ *        Specifies a pointer to the system resource header.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KeReleaseSystemResource(IN PSYSTEM_RESOURCE_HEADER ResourceHeader)
+{
+    /* Disable interrupts and acquire a spinlock */
+    ArClearInterruptFlag();
+    KeAcquireSpinLock(&KepSystemResourcesLock);
+
+    /* Release system resource */
+    ResourceHeader->Acquired = FALSE;
+
+    /* Release spinlock and enable interrupts */
+    KeReleaseSpinLock(&KepSystemResourcesLock);
+    ArSetInterruptFlag();
+}
+
+/**
+ * Initializes system resource management.
+ *
+ * @return This routine returns a status code.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+XTSTATUS
+KepInitializeSystemResources(VOID)
+{
+    PSYSTEM_RESOURCE_HEADER ResourceHeader;
+    PLIST_ENTRY ListEntry, NextListEntry;
+    ULONG ResourceSize;
+
+    /* Initialize system resources spin lock and resource list */
+    KeInitializeSpinLock(&KepSystemResourcesLock);
+    RtlInitializeListHead(&KepSystemResourcesListHead);
+
+    /* Make sure there are some system resources available */
+    if(!RtlListEmpty(&KeInitializationBlock->SystemResourcesListHead))
+    {
+        /* Iterate through system resources list */
+        ListEntry = KeInitializationBlock->SystemResourcesListHead.Flink;
+        while(ListEntry != &KeInitializationBlock->SystemResourcesListHead)
+        {
+            /* Get resource header and next list entry */
+            ResourceHeader = CONTAIN_RECORD(ListEntry, SYSTEM_RESOURCE_HEADER, ListEntry);
+            NextListEntry = ListEntry->Flink;
+
+            /* Basic resource type validation */
+            switch(ResourceHeader->ResourceType)
+            {
+                case SystemResourceFrameBuffer:
+                    /* FrameBuffer system resource */
+                    ResourceSize = sizeof(SYSTEM_RESOURCE_FRAMEBUFFER);
+                    break;
+                default:
+                    /* Unknown system resource type, return error */
+                    return STATUS_UNSUCCESSFUL;
+            }
+
+            /* Validate resource size */
+            if(ResourceHeader->ResourceSize == ResourceSize)
+            {
+                /* Move valid resource to the internal kernel list of system resources */
+                RtlRemoveEntryList(&ResourceHeader->ListEntry);
+                RtlInsertTailList(&KepSystemResourcesListHead, &ResourceHeader->ListEntry);
+            }
+
+            /* Go to the next list entry */
+            ListEntry = NextListEntry;
+        }
+    }
+
+    /* Return success */
+    return STATUS_SUCCESS;
+}
+
+/**
+ * Looks for an unacquired system resource of the specified type.
+ *
+ * @param ResourceType
+ *        Supplies system resource type.
+ *
+ * @param Acquire
+ *        Specifies whether system resource should be acquired or not.
+ *
+ * @param ResourceHeader
+ *        Specifies a memory area where a pointer to the system resource header will be stored.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KepGetSystemResource(IN SYSTEM_RESOURCE_TYPE ResourceType,
+                     IN BOOLEAN Acquire,
+                     OUT PSYSTEM_RESOURCE_HEADER *ResourceHeader)
+{
+    PSYSTEM_RESOURCE_HEADER Resource;
+    PLIST_ENTRY ListEntry;
+
+    /* Disable interrupts and acquire a spinlock */
+    ArClearInterruptFlag();
+    KeAcquireSpinLock(&KepSystemResourcesLock);
+
+    /* Iterate through system resources list */
+    ListEntry = KepSystemResourcesListHead.Flink;
+    while(ListEntry != &KepSystemResourcesListHead)
+    {
+        /* Get resource header */
+        Resource = CONTAIN_RECORD(ListEntry, SYSTEM_RESOURCE_HEADER, ListEntry);
+
+        /* Check if resource type matches and it's not already acquired */
+        if(Resource->ResourceType == ResourceType && Resource->Acquired == FALSE)
+        {
+            /* Check if resource should be acquired */
+            if(Acquire)
+            {
+                /* Mark resource as acquired */
+                Resource->Acquired = TRUE;
+            }
+
+            /* Stop browsing a list */
+            break;
+        }
+
+        /* Go to the next list entry */
+        ListEntry = ListEntry->Flink;
+    }
+
+    /* Check if resource was found */
+    if(ListEntry == &KepSystemResourcesListHead)
+    {
+        /* Resource not found, return NULL */
+        Resource = NULL;
+    }
+
+    /* Release spinlock and enable interrupts */
+    KeReleaseSpinLock(&KepSystemResourcesLock);
+    ArSetInterruptFlag();
+
+    /* Return resource header */
+    *ResourceHeader = Resource;
+}